Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BIOL 366 > Lecture 22- Plant Adaptations I > Flashcards

Lecture 22- Plant Adaptations I Flashcards

1
Q

What are some limitations to northern plants?

A
  • Short growing season
  • Drought
  • Infertile soil
  • Frost heaving
  • Permafrost
  • Snow abrasion
  • Strong winds
  • Episodic herbivory
  • Low pollinatory frequencies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What part of the short growing season limits northern plants?

A
  • Short time to put out leaves
  • Short time to release seeds
  • The temperature is consistently low, never really gets warm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What part of drought limits northern plants?

A
  • Low levels of precipitation
  • Low soil moisture levels because its frozen
  • Dry conditions
  • High winds draw out the moisture of the plant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is frost-heaving and what does it do?

A
  • Where the soil freezes and shifts
  • It is a disturbance of the soil that changes local patterns and hydrology
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is snow abrasion?

A

The mechanical damage done by snow (Weight or high winds in snow)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What part of strong winds limits northern plants?

A
  • Mechanical damage
  • Increased risk of evapotranspiration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Episodic herbivory puts pressure on what?

A

Pockets of localized pressure on plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What part of low pollinator frequencies limits northern plants?

A
  • Their reproductive success
  • Not lots of pollinator species and in low frequencies
  • Success rate of the plants is much lower
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The treeline determines what?

A

Where trees can and cannot grow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Treelines are determined by?

A
  • Lack of summer warmth
  • Restricted photosynthesis
  • Permafrost = shallow rooting depth, so doesnt support tall verticle growth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What do you find above the treeline?

A

Higher abundance of small non-woody plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In the north, annual growth is devoted to _____

A

Essentials
* Photosynthetic efforts being put into roots and leaves
* Little energy for woody tissue growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the different types of environments found in the north?

A
  • Deserts, semi-desert
  • Ice caps, glaciers, moist tundras, wet tundras
  • Shrublands, heaths
  • Bogs, marshes, salt marshes and aquatic environments
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Microhabitats allow for what in the north?

A
  • Allows for localized variation in species composition
  • Variations in topography, soil moisture and soil temperature
  • Changes in temperature, moisture, snow cover, etc
  • Small scale
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens if you shift a plant in the north?

A

Moving a plant a few centimeters might easily put it into a habitat type for which it is ill adapted to

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the three types of plant life strategies?

A
  1. Annuals
  2. Biennials
  3. Perennials
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is an annual life strategy?

A

The plant has its whole life cycle in one year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which plant life strategy is the worst and most ill adapted to the north?

A

Annual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is a biennial life strategy?

A

The plant has its entire lifecycle in two years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What do biennials do in year 1 and year 2?

A
  • Year 1 = Leaves and roots
  • Year 2 = Flowers and seeds
21
Q

List the plant life strategies from lowest to highest commonality

A
  1. Annuals
  2. Biennials
  3. Perennials
22
Q

What are perennial life strategies?

A

They are plants that are slow growing that live for many years

23
Q

What do perennials invest in the first year?

A

Invest into growth of roots

24
Q

A perennial ____ reproduce for several years

25
The majority of plants in the Arctic was what plant life strategy?
Perennial
26
Perennials generally flower every year except _____
In the first year
27
Describe a perennial root system in the north
* Many have rhizomes (for reproduction) * Roots are important for stabilization * Deep root system * Long lived root system * Often have a large tap root * Predominantly storing carbohydrates they need to keep growing
28
What are some issues that northern plants face?
* Acclimation and freezing of temperatures * Desiccation * Water supply in winter * Evergreen leaves * Mechanical problems * Reproductive strategies
29
What is acclimation?
It is a reversible change in morphology or physiology in response to environmental change
30
Plants must tolerate ____ without injury because there are no avoidance mechanisms
Freezing
31
How do plant tissues freeze?
* Undergo a multi-step process * 1st exotherm indicates ice formation in the water conducting xylem cells * Water freezes in water conducting cells * Ice crystals continue to grow as water gets drawn out of the cells * 2nd exotherm coincides with cell death and intracellular freezing * If you get freezing within the cells, it will expand and will rupture the cell wall and cause death
32
What happens to the plant if cooling is fast enough?
* Withdrawl of water from the cells cannot keep pace with rate of freezing * Ice formation may occur inside cells and cause death * Can cause a lot of splitting and rupturing of cells * Cant move the water out of cells fast enough
33
When do plants acclimate to freezing?
In late summer to early fall when the temperature starts to drop a little bit
34
Describe the process of plant tissue acclimation to freezing
* Growth cessation = stop growing (growth hormone) * Start to move sugar out of the leaves and into the roots which changes the concentration gradient inside the plant * Alteration of cellular membranes = triggered by growth inhibitors * The growth inhibitor makes the cell membrane more permeable so water can just flow out of the cells very quickly * Now water will no longer be freezing inside of the cells and causing them to rupture
35
What universal growth inhibitor increases permeability of cell membranes?
Abscisic acid (ABA)
36
What is critical for plant tissue acclimation to freezing?
Increased permeability of the cell membrane
37
Freezing injuries often occur where on plants?
Branch stubs, bark
38
Freezing injuries can cause ____ pressure
Selective pressure
39
When are freezing injuries most likely to occur?
During the growing season (late spring frost)
40
Desiccation is driven by what?
* High winds * Water vapour loss in winter (low atmospheric humidity) * Low soil moisture
41
Water loss is influenced by ____ differences between the leaf and outside air
Temperature
42
What is the rate of water loss?
Difference between water vapour concentration between internal atmosphere of leaf and outside air
43
The intracellular air spaces in leaves are near ____ humidity
100%
44
What are some morphological adaptations for desiccation?
* Short stature * Cushion grown form * Hairs * Evergreen leaves
45
What improvement does short staure offer to the plant?
* Keeps plant closer to warmth of earth * Reduces tissue exposed to high winds * Short stature keeps them in this boundary layer between the ground and the air * Keeps them lower then the bulk of the wind
46
What improvements does cushion growth offer to the plant?
* Exposed tissues reduced = less water loss * Air trapped inside cushion is warmer * Elongated taproot to replenish water loss * Can help other plants
47
What is a negative to cushion growth?
Could be susceptible to heat damage if the temperature outside is high
48
What improvements do hairs offer to the plant?
* Trap air close to the plant * Warmer temperatures adjacent to tissues * Reduce air flow across leaf surface
49
Evergreen leaves are a waxy cuticle over the leaf that ____
Reduced water loss

BIOL 366 (33 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions